Find the sum
−1/2(7z+4)+15(5z−15)

Afurniture store has 1,500 chairs in storage. a manager uses three delivery receipts to simulate samples to check 100 chairs and note the number of brown chairs. suppose the actual number of brown chairs is 1,080. about how many brown chairs are

Arestaurant gives out a scratch-off card to every customer. the probability that a customer will win a prize from a scratch-off card is 25%. design and conduct a simulation using random numbers to find the experimental probability that a customer will need more than 3 cards in order to win a prize. justify the model for your simulation, and conduct at least 10 trials.

The table shows the balance of a money market account over time. write a function that represents the balance y (in dollars) after t years.